package com.xxx.design.tutorials800;

import java.util.concurrent.atomic.AtomicReference;

/**
 * @author Hang
 * @date 2022/7/30
 * @project studydesignpatter
 * @description cas
 **/
public class Singleton_06 {
    private static final AtomicReference<Singleton_06> INSTANCE = new AtomicReference<>();

    private static Singleton_06 instance;

    private Singleton_06(){}

    public static final Singleton_06 getInstance(){
        for(;;){
            Singleton_06 instance = INSTANCE.get();
            if(null != instance) return instance;
            INSTANCE.compareAndSet(null,new Singleton_06());
            return INSTANCE.get();
        }
    }
    public static void main(String[] args) {
        System.out.println(Singleton_06.getInstance()); // org.itstack.demo.design.Singleton_06@2b193f2d
        System.out.println(Singleton_06.getInstance()); // org.itstack.demo.design.Singleton_06@2b193f2d
    }
}
